NCT05624528

A Clinical Trial of Tolcapone in Obsessive Compulsive Disorder

A Double-Blind, Randomized, Placebo-Controlled Study of Tolcapone for OCD

• Status: Active Not Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 49 (actual)
• Sponsor: University of Chicago · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Not accepted

Summary

The primary aim of the present study is to examine the efficacy and safety of tolcapone in adults with moderate to severe OCD.

Detailed description

Based on the mechanism of action and our previous pilot data, the primary aim of the present study is to examine the efficacy and safety of 8-week treatment with tolcapone vs. placebo in adults with moderate to severe OCD, as indicated by a score of at least 21 on the Yale Brown Obsessive Compulsive Scale (YBOCS), a scale of illness severity, at the baseline visit. We hypothesize that tolcapone will significantly improve symptoms of OCD compared to placebo. A secondary aim of the proposed study is to examine the cognitive effects of tolcapone in OCD, by conducting objective neuropsychological tasks pre- and post-pharmacological trial. The rationale for this approach is that: dopamine plays a key role in cognition; cognitive effects of tolcapone are likely to be relevant in explaining symptomatic effects; and cognitive dysfunction constitutes an important treatment target in OCD that is not generally ameliorated by current first-line interventions. We hypothesize that any symptomatic benefit with tolcapone would also be associated with improvement in executive functions including cognitive flexibility. Another secondary aim of the proposed study is to evaluate whether the single nucleotide polymorphism (SNP) Val-158-Met polymorphism significantly relates to changes in symptoms and cognition observed with tolcapone. Prior data indicate cognitive effects of tolcapone are affected by this SNP. We hypothesize that the val/val COMT variant will be associated with significantly higher tolcapone-related improvements in cognition and symptoms, since this is linked to lower cortical dopamine function.

Conditions

• Obsessive-Compulsive Disorder
• OCD

Interventions

Type	Name	Description
DRUG	Tolcapone	catechol-O-methyl transferase inhibitor
DRUG	Placebo	Pill that contains no medicine

Timeline

• Start date: 2023-06-22
• Primary completion: 2026-06-01
• Completion: 2026-06-01
• First posted: 2022-11-22
• Last updated: 2026-03-10

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study